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Archiver > GENEALOGY-DNA > 2005-05 > 1117604087


From: "Pendergrass, David C" <>
Subject: RE: [DNA] Middle Eastern ancestral markers on new Euro 1.0 test
Date: Wed, 1 Jun 2005 00:34:47 -0500


Andrew,

According to Hardy Weinberg population dynamics and assuming a random
mating process (ie. No endogamy), the ratio of Y-chromosomes haplogroups
from one ancestor to another to another would persist from one
generation to the next. The ONLY way to change the ratio is through a
selective advantage. Endogamy violates the random mating process
assumption because it means that marriage and reproduction are kept to a
certain group based upon environmental cues (religion, for example).

It certainly is possible for a y-chromosome haplogroup to die out if
it is significantly less than the other y-chromosomes in the population
in a selection-deficient population. But this would occur simply by
chance. For example, suppose you have a million people with certain Y
haplogroups, but only 8 people with a T1a (made-up!). By chance those 8
people ended up with all females. The T1a group would then be lost. To
give you the probability, (1/2)**8, 1/256 chance if each had one child.
Let's suppose that only 1 person had the T1a and one child. Then, there
would be a 1/2 chance. Clearly, the more that have the T1a haplogroup,
the less likely the loss of the haplogroup to extinction. Unless, of
course, the T1a haplogroup has a selection disadvantage.

David P.

-----Original Message-----
From: Andrew and Inge [mailto:]
Sent: Wednesday, June 01, 2005 12:10 AM
To:
Subject: RE: [DNA] Middle Eastern ancestral markers on new Euro 1.0 test


Ray

What is so astonishing about it? If John or you accept that a single
paternal line or a small group of paternal lines can die out then what
is the *qualitative* difference that makes it impossible for a big group
to die out by chance - or to put it in John's terms, why is it
necessarily proven that any paternal line which has become a majority
group *must* have a selective advantage. I think the basic logic already
speaks for itself and the burden of proof lies with John, who starts his
argument with "trust me" and also claims he can show the maths.

Andrew

-----Original Message-----
From: Raymond Whritenour [mailto:]
Sent: Wednesday, 1 June 2005 1:16 AM
To:
Subject: [DNA] Middle Eastern ancestral markers on new Euro 1.0 test


Andrew wrote:

"I don't have any references but I am aware of the fact, from reading
something in the past, that a simple random computer programe which
assumes no selective advantage will show surnames or Y DNA dieing out
even when they have been in a majority situation."

Andrew!

You've got to find out where you read this, and cite the source for us!
You can't make an astonishing statement like this and expect us to
simply accept it! If this is true, I want to know the details.

Ray Whritenour

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